^Pennsylvania. Dept. of General Services؛ Pennsylvania. Bureau of Publications؛ Pennsylvania. Dept. of Property and Supplies (1976). The Pennsylvania Manual. Department of General Services. ج. 103. ISSN:0275-8814. مؤرشف من الأصل في 2016-05-02. اطلع عليه بتاريخ 2015-02-27.